Lottery is a form of gambling in which participants pay to purchase a ticket that contains numbers or symbols, or enters them into machines that randomly dispense prizes to those with matching numbers or symbols. It has a long history and has been a major source of revenue for states. In addition to its popularity, lottery is a topic of intense debate and study because of its potential for compulsive gambling, its regressive impact on low-income households, and other issues of public policy.

Since New Hampshire initiated the modern era of state lotteries in 1964, nearly every state has adopted one. They all follow the same basic pattern: The state legislates a monopoly for itself; establishes a state agency or public corporation to run it; starts with a small number of relatively simple games; and progressively expands its operations and game offerings to increase sales.

During the period in which lotteries have been most popular, the state governments have used them to raise money for a broad array of purposes, from building bridges and roads to paying off debt. They have argued that lottery proceeds are more reliable than tax increases or cuts to other programs, and they have won broad public support.

But even though lottery revenues are more reliable than many other sources of revenue, they do not ensure that the state will be able to meet its obligations to its citizens. And despite the fact that gambling is inevitable, and the odds of winning a lottery prize are determined by a process whose outcome depends entirely on chance, the lottery remains at cross-purposes with public interest.